Carcassman -
I too recall that the coded wire tags (CWTs) were used then and that the adipose fin clip was sequestered for only those fish with the CWTs., In fact it took a couple of years effort to get the approval (from PFMC) to use the adipose fin clip for mass marking rather than for CWTs. That delayed the mass marking of PS steelhead a couple of years.

GBL -
Another thing that was going on during the 1970s was the rapid increase in the fisheries off the west coast of Vancouver Island. By the late 1970s those fisheries were taking huge numbers of Puget Sound coho (and Chinook).

I agree that such fry programs are excellent "feel good" programs that have some educational value. In addition those wild brood stock programs were great fun; especially when those involved got to fish closed waters. In fact about the only time that support for that type of program waned was when those "experimental" programs became the "norm" and the expected production (returning adults) were included in management - forecasts, # of harvestable fish, etc. The result of course was that terminal fisheries and even worst the escapements relied on those "paper fish". That of course fosters continued over-fishing/under escaements.

Tight lines
Curt