I don't have to speculate because there are lots of examples of where smallmouth bass move into salmon rivers. Once they're there, they never leave. They do impact. As they get bigger, they will predate on young salmon, but they will also take the habitat that young salmon require to grow. In a watershed like the Miramichi, where we have some very cold water and high streams, maybe they'll not go there, but the main trunk of the rivers will be infested with smallmouth bass.
On May 6th, 2019. See this statement in context.