SG-
Think something is amiss with your math. AT 6 smolts/pound and a cost of $10/pound it would cost $1.67 per smolt. At a 0.4% smolt to adult survival it would take 250 smolts to produce a single adult steelhead. 250 times $1.67 equals a cost of $417.50 per adult.

That may still make economic sense. I see that the 2017 WDFW Hoh river steelhead creel survey it took over 5 angler days to catch a single steelhead.

Curt