Hatchery Fish and Wild Fish Naturally Segregate

Interesting read that makes you wonder.

https://idfg.idaho.gov/press/research-fi...tes-after-being

That is a interesting read! In fact for a short article it certainly provides a lot of food for thought.

Interesting about the segregation in rivers. I’ve wondered if that was the case for a long time. I know with Coho in specific, I can be catching and releasing wild fish for hours, and then suddenly crack into a hatchery fish. At that time, we’ll generally anchor up and find our limits between there and the next few hundred yards down river, finding almost nothing BUT hatchery fish.

We need more of this kind of work. Looks interesting. As I recall, WDG tagged steelhead at Kalama Falls and there were fisheries above. Don't know if they looked at the rec catch.

I thought, at least conventional was, that steelhead were hard to catch. Exploitation rates of 33% for wild and over 50% for hatchery don't seem low to me.

As to catching more than once, a friend was out sampling steelhead. Catch, take scales, get a DNA sample, release. Caught this dude on a fly, worked him up, released him, and cast the same fly at him. Caught him again, hit the first cast.

Just goes to show you, not all what we know is the gospel and shouldn't be implemented as such. Steelhead stray and always have, and are not watershed specific. So the notion of past hatchery practices being taboo, by speading Chambers Steelhead everywhere is BS. It worked then and I bet it would work now if allowed. Then we could again have an early component opportunity like there used to be.

Rungun, agree and agree. Plant more fish.

As always, the details are important!

The study says that 33% of tags placed on the wild fish were returned anglers and 55% of the tags placed on hatchery fish were returned. Because the anglers were voluntarily returning the tag information those rates would the floor estimate of the encounter rates.

More importantly in discussing the difference in recoveries of tags from hatchery and wild fish "Lubenau said the reason for that is fairly simple. The two types of steelhead tend to naturally segregate in the river, and anglers focus more attention and effort on hatchery steelhead."

Anyone who have spent much time on rivers with a hatchery terminal area (release site) would quickly recognize that the catch in those areas is dominated by hatchery fish. The wild fish are more broadly distributed while many of the hatchery fish are more clustered near those release/rearing sites.

The real news in this study is the confirmation that the wild steelhead catch and release mortality of 5% used by the managers is reasonable. The measured mortality was 4%.

Curt