Well... Salmon will not eat.
The only ime they do is out of agression, and it's more of a bite and spit it out thing.
Cut open a salmon stomach and see what you find, NOTHING in every single one.
Steelhead on the other hand will eat.
Kelts are the most likely candidates, but you wouldn't eat those things anyways.... I hope
And I rarley fish the Fraser, but all fish come through there so it doesn't matter where you fish.
As far as carp go, have you ever touched one? They are twice as bad a salmon and they actully wreak worse than a white.