Wow, that's an impressive report. I must admit I got bogged down in the statistics. They use some that are above the level I ever got to in undergrad school. I don't lament the Kostow study so much; this one has a larger data set and takes a deeper dive into ocean survival variables. Interesting that they found no correlation with May upwelling, which intuitively seems influencing to me, yet did find a correlation with May PDO. Kostow looked at PDO for the period of ocean residence, which in more intuitive and makes sense as a variable affecting total marine survival. Who'da' thunk to examine May PDO as a discreet independent variable? Probably not me.

This report doesn't have all the answers either, but it's important. I've figured all along that the presence of hatchery fish doesn't do any favors to wild fish, but I haven't thought the hatchery fish are a limiting factor either. Looks like they aren't, at least in the Clackamas. I think that's the case in most WA streams as well. The problem with hatchery steelhead in WA looks to be that they don't return enough adult fish to justify the expense of having them as a taxpayer and license funded program.