There is an area near where I live called Indian Heaven. Lots of huckleberry fields and camas lilies grow wild (natives ate the roots). And historically wild salmon was plentiful.
Sounds good to me.
It should have been obvious to any man of science that if humans settled in a place for any length of time that the food and other resources necessary for life had to be there in the abundance necessary for a substantial number of humans to survive.
Humans can not subsist on one food source or even a few food sources. If the natives were drying fish, which they would have to do if that was their primary protein source, there had to be ample other food stuffs available in the area.
People without the wheel can’t transport large stores of dried fish from one place to another.