Part of the problem is we damn well know how many fish we need to have returning to PS (entering the Straits) for the SRKWs. WDFW has (I know they had) a data base of adult salmon of all species and timings entering PS from the late 60s/early 70s. It includes hatchery and wild so you know the fish numbers. Pretty sure WDG had steelhead numbers but it was more likely catch as I am not sure they really did escapement numbers until Boldt. But, that is still a long-term data set. You can convert that to biomass, as you have the catch data, and even the timing so you know day to day what adult biomass was available. You can add to that the Fraser pink and sockeye, which goes back even further. I don't know how good the DFO data is for Fraser and southern BC adults, but they must have something.

That can be compared to the known numbers of whales. The problem is finding the huevos to ensure that many adult salmon return.