It is not clear from the article how they are separating wild from hatchery fish or if the method is 100% accurate.

The figure caption is a real laugh - see the last six words: "People on the West Coast have counted on fish hatcheries for more than a century to help rebuild populations of salmon and steelhead and bring them to a level where government would no longer need to regulate fisheries."
Does this remind you of a certain Spanish knight?