Non-selective fishing, combined with hatchery production, has been shown to wipe out the wild stocks. Hatchery stocks can be harvested at 90-95% of the adult returns. The wild stocks cannot be harvested at anything close to that. If fishing is non-selective, the wild fish will be harvested at the same rate as the hatchery fish. So one of two things happen. Either there is a huge, unharvested population of hatchery fish; or the wild stocks go extinct.

Which do you think will happen?

Lemme answer my own question:

History is clear. When a watershed contains a fish hatchery, all stocks are harvested at the higher rate. And the wild fish are quickly eliminated. That is the legacy of non-selective fishing, and hatchery production.