Since Vikki asked and I've been asked before, I wanted to explain fish decoys and how they're used. Pictured above is a trout decoy. The stick is called a "jigging stick" and, unlike this one, can often be intricately carved itself. The decoy is hollowed out on the underside and filled with some sort of weight, either washers or lead or something. This makes the fish neutrally buoyant so that it "swims" like a real fish. Forgive the poor quality of the picture, but here you can see what it looks like:A hole is cut in the ice, much larger than if you were using a line and hook. The fisherperson "swims" the fish around in small circles to attract other fish. He holds the jigging stick (unlike this yahoo in the picture) which is attached to a short line which is attached to the top of the decoy. When other fish come near, they spear them with that trident-looking thing. It is a lot more involved than sitting and watching a line for nibbles.
I have never done this, but I know of it through my involvement with fishcarving. Calling my fish "decoys" is probably misleading. Most of the fish I carve are purely decorative. I've only ever carved one working decoy. For those of you that haven't seen them, there is a link on the side to pictures of my work.