Not mutually exclusive nor black-and-white. The world, including the world of hatchery produced fish, is complex.

I have a sub-basin project where the desired outcome is naturally self-sustaining coho. The run was very depressed, and we have used hatchery produced fish to recover it. This is a hydro project, and while juvenile out-migration is much improved, it is not perfect. Furthermore, these fish are subjected to whatever pre-terminal and terminal area fisheries the adjacent stocks of coho are subjected to. What it has come down to is that about half the time the stock could sustain itself without hatchery supplementation. And the other half it comes up short on wild fish escapement without the supplemental hatchery fish, and even sometimes with them. The upshot is that complete recovery without the supplemental hatchery fish does not appear to be an option. Without those hatchery fish in some years, the wild stock will begin slipping back to a depressed status.

I can think of several other salmon and steelhead populations where hatchery supplementation provides harvestable fish, or extra harvestable fish in some years, and are a critical insurance policy for long term sustainability in others.

Sg