Freespool,

When harvest is the limiting factor, populations do respond quickly as soon as the over-fishing is discontinued. For instance, as soon as spring spill is used instead of no spill and forcing smolts to use turbine passage or barging, fish populations respond with higher survival due to, duh!, lower mortalities.

Carcassman,

I cannot be certain, but I think egg to fry at 50+% even in pristine times is unrealistically high. The best I've been able to estimate is 30-36%, but that is much better than the 12% or less that has become common for many salmon in contemporary times. The proof is in the evidence that many wild coho and chinook populations used to be able to sustain harvest rates of 75 and 80%. Now we have a lot of populations that cannot sustain 40% and even less. Clearly the survival rates at several life stages are reduced from former times.

Sg