Caddis hatch in a variety of sizes and colors and can be found worldwide in big rivers, small streams, and even lakes. They live as a stationary larvae most of their lives on the bottom with very little movement, they cling to rocks or other debris and typically build a shell or shuck out of organic debris and small gravel. Caddis are Periwinkles and vice versa. When they hatch Caddis tend to move to the surface quite quickly, and emerge very fast so the takes are often splashy and aggressive. Anglers should have a good balance of larvae, pupae, emergers, and adult patterns for the various stages of the hatch.