Steelhead and coho rarely use the same water to spawn given the choice - steelhead are mainstem, big water spawners like chinook, and coho prefer to spawn as far up the system and in the tiniest rills possible.

The Snyder and Satsop programs do appear to produce survivors, but both of these systems have decent habitat, large refuge areas, are not netted except at the mouth, and the Satsop is all wild fish release while on the Duc most people release wild fish and bonk the brats. Wild fish populations by and large are already healthy in these systems, and are likely the majority of spawners. This promotes diversity and prevents genetic drift towards undesirable hatchery traits.

Contrast this with those rivers, like the one in the Oregon study, that have mostly hatchery fish and have habitat problems, like dams. Hatchery fish likely comprise the majority on the limited spawning beds most years, thus perpuating domestic traits that lead to lower survival.

Now I ask you this - in a river with good habitat and wild fish release, is a hatchery stock desirable? I would say no, not for the fish but hell yes for the fishermen! That being the case, would it be better for the wild fish to have a hatchery stock that spawned too early to co-mingle with them, or one that spawned right with them. I would say the former. Myself, I like it that way - catch my chrome keepers all in a pile and get the fish processing over with, and fish for fun the rest of the season. I start getting hungry for fresh meat mid-Feb? Well I'm going blackmouth fishing tomorrow