Reading over this gargantuan thread and not having much to add to the conversation I would like to pose a question to the contributers here.

It seems a large amount of stock is being thrown into good vs. poor ocean conditions. With the Pacific Ocean being the enormous body of water it is, many different species of salmonoids migrating to different parts of the Pacific, and many different aquatic species inhabiting the Pacific that affect the food chain. How is it that ocean conditions are absolutely determined to be good or bad in any given year? Who makes this determination? How reliable is the data? What kind of data is used?

Seems to be an important part of the equation here. Just wondering how such an enormous assessment is made year to year?

Thank you for all who have contributed. Lots of info to soak up for someone with an interest in this topic.