Micro, do you have any evidence that wild steelehead genetics is influeced by hatchery strains? If so, what is it?

I think the main genetic influence of hatchery fish on wild genetics is to improve sexual selection of wild fish. If you're a wild fish and you choose a hatchery mate, you're not going to be successful. Therefore, wild fish are probably more likely now to choose only other wild fish as mates where both hatchery and wild fish are present. Ie I suspect wild fish spawn later now than before hatcheries were present. That is proabably the simplest strategy for a wild fish to avoid spawning with a hatchery fish.

RA3, Aunty M, I think there is some evidence, that if you delay the outmigration of smolts, then many of them stay in the river and become resident fish. That's the last thing you want to have happen if you're trying to avoid hatchery fish eating wild fish.

Maybe Salmo g or Smalma could comment on the above.