Ah, the broodstocking debate. Here's the thing...The whole notion of boodstocking as a way of supplementing "wild" fish is a great idea, but you have to understand that the method in itself introduces unnatural components into the fishes genome.

First, for efficiencies sake, eggs and milt from relatively few fish are taken, much much fewer than the number of naturally reproducing adults. This automatically makes the gene pool of the brood stock less robust then naturally reproduced wild fish. Second, there is significant natural selection going on (or unnatural selection) when you dramatically increase the egg to smolt survival rate by rearing the juveniles in a protected environment. Many of those naturally reproduced juvenile fish that don't survive for whatever reason--predation, competition, disease, etc.,--would survive in the hatchery, thus lowering the genetic fitness of the stock if they return as adults. In this sense, only a single generation of broodstocking can introduce genetic changes.

That said, I'm still a proponent of brood stock programs with hatchery reforms in place. Collecting fish for broodstock should be conducted with a goal of maximizing genetic fitness and diversity as oppose to merely getting enough eggs to fill the raceway with smolts. I also don't believe you have the same potential for population declines when broodstocked fish and wild fish interact and reproduce naturally, compared to when you have traditional hatchery fish and wild fish interact. But realize that the broodstocked fish are not genetically "wild" for the above reasons, so interaction should be kept to a minimum. There is a potential problem in this, because brood stock fish are not separated temporally from the wild fish (i.e., early returners), so there is more difficulty in keeping the stocks from interacting.

I'm not familiar with the mechanics of brood stock programs, but there should be a component of true wild fish taken out of the river each season and added to brood stock returns to keep genetic diversity as high as possible, while keeping the efficiencies of hatchery production.