[Quail1]

This is a Sockeye(Red)hen. Relatively quickly after the salmon hit fresh water they begin the transformation. After the hens have dropped their eggs, males and females quickly move to this stage and become more and more lethargic. Until they ultimately die or are eaten by bears, eagles, etc.
The bears move from rivers that hold no more salmon to others that have later runs. Soon this is all that is left to show that any where there at all.