Just to be clear, the southern residents don't just 'live in Puget Sound', they are migratory and move between Monterey CA and southeast Alaska. https://www.nwfsc.noaa.gov/research/divi…
But they definitely need more salmon to eat. If habitat were not as degraded as it is in Puget Sound it might be able to send them onto their winter travels in better condition than they currently experience.
Here is a University of Washington website where you can look at total returns of species of salmon in the Columbia, among other things. Please compare how many are returning recently vs back in the 1930s: http://www.cbr.washington.edu/dart/query… One thing your article did not address was the devastating effects of industrial fishing, which started in the 1860s. This is what brought numbers crashing from >10 million down to less than a million by the 1920s. You also are failing to even mention the Hells canyon dams have no fish ladders, and these are the ones that block a lot of Snake salmon habitat, while the lower Snake dams have good passage rates. http://www.nrcresearchpress.com/doi/abs/…
But they definitely need more salmon to eat. If habitat were not as degraded as it is in Puget Sound it might be able to send them onto their winter travels in better condition than they currently experience.