 When fishing on rivers for game fish, i.e.brown, rainbow, brook and sea trout, salmon and in some cases grayling (game status debated), artificial flies, small spinners and lures are a popular choice for many game anglers due to the way they intentionally mimic a fly or small fish on the surface and top layers of the water, enticing the fish into feeding as it sits among actual live flies and fish fry.Both floating and sinking flies and lures can be used to fish either on the surface or in the upper layers of the water.