Elbow: One thing I know for sure is that this is a complex subject. Why did we have great returns a few years ago in the Columbia system? Hell I don't know, but I know that in some cases, at least in the short term, global warming can be beneficial to salmon. For example, if we have systems that suffer from low flows, and the warming trend cause more rain in those basins flows improve. At the same time warming in other basins can cause flooding and harmful water temps. It may be that the good returns were not related to global warming at all.

One thing I am sure of is we can't look at only a year or two to access long-term trends.

As for dams hurting salmon, I don’t believe that discussion is part of this one and will leave that for another thread. You may want to post that as an independent topic.