Hi,
i use to hunt a lot in river when i was in Quebec. The big difference is that the fish can only evade you going up or down the river. This call for a different type of hunting that i would call skeet shooting. Basicly (how do you write that) you go up the river and shoot at the fish when you see them. The river i was hunting in was 2 m deep and 10 m wide. In a river, most of the fish will have a spot where they return all the time. So if you miss the fish, you go back to where you saw it and bye bye
You need to go up the river so if a fish pass by you, it will be easier to turn around,engage pursuit and accelerate going downstream. Also, it's harder for the fish to outrun your arrow when they have to go upstream because danger's coming from downstream.
Since most of the shot are point blank and fast, i would recommend a smaller gun.