What is the theme in The River Why by David James Duncan?

Fishing is the main theme of this story. The concept of fishing is an important one throughout the novel. Gus is a fishing prodigy who comes from two parents who fish—albeit in directly opposite fashions. The dichotomy between Ma's direct bait-and-hook approach and H20's fluid, elaborate fly-fishing style produces a unique fisherman in Gus. He is proficient in both styles, but cannot tell either parent how he caught his fish without a debate brewing in his household. Fishing is the platform on which all conversations and communication is held in the Orviston family. And until the destruction of Nijinsky, their different styles of fishing do little more than cause strife in the family. When Gus destroys Nijinsky, H20 and Ma are suddenly open to the idea of fishing in the other's style, quelling the flames of debate that raged for decades in their house.